cxl/pci: Find and register CXL PMU devices

CXL PMU devices can be found from entries in the Register
Locator DVSEC.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230526095824.16336-4-Jonathan.Cameron@huawei.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

5 files changed, 88 insertions, 0 deletions

diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index ca4ae31d8f57..1f66b5d4d935 100644
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -12,5 +12,6 @@ cxl_core-y += memdev.o
 cxl_core-y += mbox.o
 cxl_core-y += pci.o
 cxl_core-y += hdm.o
+cxl_core-y += pmu.o
 cxl_core-$(CONFIG_TRACING) += trace.o
 cxl_core-$(CONFIG_CXL_REGION) += region.o
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
index 27f0968449de..99d4a967eca6 100644
--- a/drivers/cxl/core/core.h
+++ b/drivers/cxl/core/core.h
@@ -6,6 +6,7 @@
 
 extern const struct device_type cxl_nvdimm_bridge_type;
 extern const struct device_type cxl_nvdimm_type;
+extern const struct device_type cxl_pmu_type;
 
 extern struct attribute_group cxl_base_attribute_group;
 
diff --git a/drivers/cxl/core/pmu.c b/drivers/cxl/core/pmu.c
new file mode 100644
index 000000000000..7684c843e5a5
--- /dev/null
+++ b/drivers/cxl/core/pmu.c
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2023 Huawei. All rights reserved. */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <cxlmem.h>
+#include <pmu.h>
+#include <cxl.h>
+#include "core.h"
+
+static void cxl_pmu_release(struct device *dev)
+{
+	struct cxl_pmu *pmu = to_cxl_pmu(dev);
+
+	kfree(pmu);
+}
+
+const struct device_type cxl_pmu_type = {
+	.name = "cxl_pmu",
+	.release = cxl_pmu_release,
+};
+
+static void remove_dev(void *dev)
+{
+	device_del(dev);
+}
+
+int devm_cxl_pmu_add(struct device *parent, struct cxl_pmu_regs *regs,
+		     int assoc_id, int index, enum cxl_pmu_type type)
+{
+	struct cxl_pmu *pmu;
+	struct device *dev;
+	int rc;
+
+	pmu = kzalloc(sizeof(*pmu), GFP_KERNEL);
+	if (!pmu)
+		return -ENOMEM;
+
+	pmu->assoc_id = assoc_id;
+	pmu->index = index;
+	pmu->type = type;
+	pmu->base = regs->pmu;
+	dev = &pmu->dev;
+	device_initialize(dev);
+	device_set_pm_not_required(dev);
+	dev->parent = parent;
+	dev->bus = &cxl_bus_type;
+	dev->type = &cxl_pmu_type;
+	switch (pmu->type) {
+	case CXL_PMU_MEMDEV:
+		rc = dev_set_name(dev, "pmu_mem%d.%d", assoc_id, index);
+		break;
+	}
+	if (rc)
+		goto err;
+
+	rc = device_add(dev);
+	if (rc)
+		goto err;
+
+	return devm_add_action_or_reset(parent, remove_dev, dev);
+
+err:
+	put_device(&pmu->dev);
+	return rc;
+}
+EXPORT_SYMBOL_NS_GPL(devm_cxl_pmu_add, CXL);
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index e7c284c890bc..f8b2b174086e 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -56,6 +56,8 @@ static int cxl_device_id(const struct device *dev)
 		return CXL_DEVICE_MEMORY_EXPANDER;
 	if (dev->type == CXL_REGION_TYPE())
 		return CXL_DEVICE_REGION;
+	if (dev->type == &cxl_pmu_type)
+		return CXL_DEVICE_PMU;
 	return 0;
 }
 
diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c
index 4b9672db867d..518bc2ad2c1e 100644
--- a/drivers/cxl/core/regs.c
+++ b/drivers/cxl/core/regs.c
@@ -6,6 +6,7 @@
 #include <linux/pci.h>
 #include <cxlmem.h>
 #include <cxlpci.h>
+#include <pmu.h>
 
 #include "core.h"
 
@@ -379,6 +380,21 @@ int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_count_regblock, CXL);
 
+int cxl_map_pmu_regs(struct pci_dev *pdev, struct cxl_pmu_regs *regs,
+		     struct cxl_register_map *map)
+{
+	struct device *dev = &pdev->dev;
+	resource_size_t phys_addr;
+
+	phys_addr = map->resource;
+	regs->pmu = devm_cxl_iomap_block(dev, phys_addr, CXL_PMU_REGMAP_SIZE);
+	if (!regs->pmu)
+		return -ENOMEM;
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_map_pmu_regs, CXL);
+
 resource_size_t cxl_rcrb_to_component(struct device *dev,
 				      resource_size_t rcrb,
 				      enum cxl_rcrb which)